The Gladiators found themselves 16 points down on the scoreboard with a little over 10 minutes played before mounting an encouraging fightback.
The visitors, who play three division above Chester, used all their experience to take advantage of some slack home defence and seize control of the game.
However, the Gladiators eventually stemmed the tide and began to work their way back into the game.
Tries from Dan Rowett and man of the match Tom Bradfield, either side of a fourth St Anne's score, restored Chester's pride before the half time break.
Oldham extended their lead with the opening try of the second period before two quickfire Gladiators tries.
Dan Timperley slid over for his first try for the club on 54 minutes and from the resulting kick off Bradfield burst clear before setting up Rowett for the easiest of touchdowns under the posts.
Oldham scored next to strengthen their advantage before Chester's loose forward Steve Threlfall scored an outstanding solo try to keep the Gladiators fading hopes alive.
Chester pushed forward in the final few minutes but Oldham ran in two tries late on to seal a 42-28 win.